US573924A - Fire-alarm system - Google Patents

Fire-alarm system Download PDF

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US573924A
US573924A US573924DA US573924A US 573924 A US573924 A US 573924A US 573924D A US573924D A US 573924DA US 573924 A US573924 A US 573924A
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fire
box
circuit
annunciator
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    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B27/00Alarm systems in which the alarm condition is signalled from a central station to a plurality of substations

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  • ROGERS Fire- Alarm System
  • This invention relates to fire-alarm systems for town and city use; and it has for its object to provide an improved system of this character whereby the different fire-stations and central oflice will be immediately notified of the number of the particular fire-alarm box from which the alarm was turned in without. having to wait until the gong in the station tolls off the number of the box, as is now the case in connection with most firealarm systems in general use.
  • the invention also contemplates, among other objects, an improved arrangement whereby even though a break should occur in the main line at either side of a particular fire-alarm box or in the annunciator-wire for such box the latter would not be rendered inoperative, but would still send in an alarm when manipulated in the usual way; and in the attainment of this very important object the invention also contemplates means for determining where the break is located, and also providing telegraphic communication throughout the'ent-ire system and also with the general gong or whistle, whereby an alarm may be sounded from the central station or office.
  • Figure 1 is a diagrammatic view of the system shown in circuit with only the central station or oflice.
  • Fig. 2 is a detail elevation of an ordinary fire alarm box equipped with a circuit-breaker constructed in accordance with this invent-ion.
  • Fig. 3 is a detail elevation of the circuit-breaker, show ing the parts positioned so as to close the cir cuit between one of the main-line terminals in the box and the ann unciator-wire terminal.
  • Fig.4 is a similar View to Fig. 3, with the exto close the circuit between the other of the main-line terminals in the box and the annunciator-wire terminal.
  • Fig. 5 is a detail plan view of the circuit-breaker device.
  • main-line wire a has two terminal connections with each of the fire-alarm boxes, and it will also be understood that any number of said boxes may be included in the circuit of the main line,but for convenience in understanding the system only three of the fire-alarm boxes are illustrated and are conveniently designated by the numerals which will also represent the numbers that the particular boxes are known by in the system.
  • the main-line wire a has one of its terminals lead to the fire-station 1, which will be understood to be the central fire-station or ofiice, and at which point this terminal of the main-line wire is suitably connected to one end of the switch-lever 2 of a three'point switch 3, provided with the three contactpoints 4, 5, and 6, with each of which points the swinging end of the switch-lever 2 is designed to contact to provide for making the proper circuit connections'in controlling the system.
  • the lever 2 is positioned to contact with the point 4., with which contact-point is connected one terminal of the battery-wire b, the other terminal of which wire connects to one pole of the working battery 7.
  • the other pole of this battery has connected thereto one terminalof the batterywire 0, the other terminal of which wire connects with a switch-lever S of a two-point cutout switch 9, having the two contact-points 10 and 11. 9 has connected thereto one terminal of the The contactepoint 10 of the switch short-circuit wire d, the other terminal of Which connects with the wire 6, which wire is connected with the intermediate contactpoint 5 of the switch 3, and at its terminal opposite the connection with the point 5 with the main-line wire a, near the terminal thereof, opposite the terminal connected with the switch-lever 2.
  • the contact-point 11 of the switch 9 has connected thereto one terminal of the gon g-wiref, leading to the electric station-gen g 12, which is arranged at the fire-station with the other controlling apparatus and is set on a closed circuit, so as to operate and sound an alarm when the circuit in which the gong is included is broken.
  • a gong-wire 9 leads from the station-gong 12 to the switch-lever 13 of a cutout switch 14, providedwith the two contactpoints 15 and 16, respectively.
  • the contactpoints 15 and the switch 1t have connected thereto a short-circuit wire it, which also connects with the wire 6, and the contact-point 16 has connected thereto one terminal of the wire '11, the other terminal of which connects with an electrical general gong or whistle 17, to the controlling mechanism of which is also connected the terminal of the main-line wire a 0p posite the terminal connected with the switch
  • the general gong or whistle 17 is illustrated as being an ordinary steam-whistle controlled by suitably-operated mechanism which is set on a closed circuit, so as to operate and sound the whistle when the circuit in which such whistle is included is broken, and at this point it may be observed that steam-whistles of this character are isolated at some convenient point in the city or town, so that the fire-alarm can be easily heard within any reasonable dis tance, but it will of course be understood that the whistle may be substituted for by an ordinary electric gong intended to accomplish the same result.
  • the pole of the working battery 7, to which the wire Z) leads also has connected therewith one terminal of the return-wire j of an ordinary annunciator or indicator 18, pro-,
  • the annunciator 18 is illustrated as being provided with four drops, one each for the fire-alarm boxes 52, 53, and 54, and one for a special call, such as for an engine, a reel, &c.; and it will of course be understood that the annunciator will be provided with any number of drops for special calls and with the requisite number of drops for the fire-alarm boxes.
  • the drops 19 for the fire-alarm boxes are provided with the numbers of these boxes, so that the moment a drop is released and shows its number at the fire-station it will immediately indicate the number of the firealarm box from which the alarm was turned in, so that the firemen will not be compelled to wait until the gong has tolled off the num-' ber of the fire-alarm box before starting to the fire, which is an item of considerable importance in fire-alarm systems.
  • Each of the fire-alarm boxes has a separate annunciator-wire leading thereto, which annunciator-wire also connects with the annunciator and controls the particular drop having the same number as the fire-alarm box to which the wire leads, so it will therefore be seen that there is a direct annunciator-wire connection between the annunciator at the fire-station and each fire-alarm box, although it will be understood that the entire series of annunciator-wires may be run out from the station in a cable, as is customary in stringing wires.
  • an ordinary telegraphic key 21 is employed.
  • the key proper of the telegraphic key has a wire connection 1 with the wire a, and the contact-point 22 of the telegraphic key has connected thereto one terminal of the switch-wire m the other ter minal of which wire connects with a switchlever 23 of a switch 2t, provided with a numberof separate contact-points 25, which correspend in number to the number of fire-alarm boxes and special calls which are indicated by the annunciator 18.
  • the separate contact-points 25 of the switch 24 have separate wire connections a, respectively, with each of the annunciator-wires and with the special drop which the annunciator is illustrated as being provided with, and the special-wire connection between one of the contact-points of the switch 24 and the annunciator may be additionally designated by the referencecharactcr 92/.
  • Fig. 2 of the drawings simply indicates diagrammatically in dotted lines the mechanism 27, which is found in all firealarm boxes.
  • circuitbreaker 28 which circuit-breaker necessarily provides for a different arrangement of the wire-terminals leading into the boxes.
  • circuit-breaker 28 essentially consists of a contact-disk 29, mounted on one of the shafts of the mechanism 27, so that when the a controlling lever or hook of the mechanism is pulled to set the latter in motion a rotation will necessarily be imparted to the contact-disk 29.
  • the contact-disk 29 is provided on its periphery with spaced groups of contact-teeth 30, which teeth are grouped in substantially the same manner as in the circuitbreakers in common use, it being understood that the number of teeth in each group corresponds to one of the figures of the particular number of the fire-alarm box in which the circuit-breaker is arranged.
  • the disk 29 is represented as being provided with spaced groups of respectively five and two teeth, which make the number 52, which is the number of the fire-alarm box illustrated in Fig. 2 of the drawings.
  • the rotatingcontact-disk 29 is suitably insulated from the shaft 30 and is provided at one side of the teeth 30 with an outer smooth contact portion 31, on which bears one end of the spring contact-brush 32, to whichis connected one of the terminals ct of theline-wire leading into the box, and the other terminal CL2 of the line-wire leading into the box is connected to the opposite spring contact-brush 33, one end of which is adapted to bear on and ride over the contact-teeth 30 of the disk.
  • the wire-terminal ct connected with the brush 32, is always the terminal of that portion of the main-line wire which leads from the general gong or whistle, in order that the proper circuit connections may be made, as will be hereinafter more fully understood, and in conjunction with the brushes 32 and 33, connected, respectively, with the wire-terminals c and a is employed an annunciator-wire brush 3*, to which connects the terminal of the annunciator-wire leading into the box.
  • the annunciator-wire brush 34 is also adapted to ride over and contact with the contact-teeth of the disk, but does not contact with the disk between the groups of teeth. So, therefore, it will be observed by reference to Fig. 2 of the drawings that when the mechanism in the fire-alarm box is at rest the annunciator-circuit will remain open while the main-line circuit will be closed through the medium of the metallic disk 29, which provides a metallic connection between the brushes 32 and 33 for the main-line wire, and since the main-line circuit is normally closed in the manner described both of the brushes 32 and 33 are designed to normally always contact with the disk.
  • an auxiliary contact-disk 35 which is insulated from the shaft 30 in the same manner as the disk 29, and is provided at one side with a series of offstanding contact-pins 36, which project into the spaces between the teeth 30 of the disk 29, and said auxiliary contact-disk 35 has normally contactintherewith the supplemental contact-brush 33, forming a part of the brush 33, which rides over the teeth 30.
  • the main-line circuit referred to includes the battery 7, wire a, cut-out switch 9, station-gong 12, cut-out switch 14, general gong or whistle 17, the main-line wire a, switch 3, and battery-wire 1).
  • the switching of the circuit in the manner described will provide means whereby all of the firealarm boxes will operate in the same manner as if no break had occurred.
  • the main-line circuit will be combined with the annunciator-circuit to complete a continuous circuit, it being noted that with respect to the box 53 that portionof the main line is broken which has a terminal connection a with the brush Consequently as the disk 29 continues to rotate the circuit will be alternately opened and closed between the brushes 32 and 34, and this circuit will include the battery 7, wire a, switch 9, station-gong 12, switch 14, wire 2', general gong or whistle 17, wire a, and terminal ct of said wire, annunciator-wire 7t, annunciator 18,
  • the circuit Since the circuit is opened and closed between the brushes 33 and 34 when the alarm is turned in from the box 54, at one side of the break B, the circuit will include the battery 7, wire 0, switch 9, station-gong 12, switch 14, wire '5, general gong or whistle 17, wire a, wire 2, lever 2 of switch 3, wire a, terminal a in box 54, annunciator-wire for said box, annunciator 18, and wirej.
  • the operator at the box 54 can determine whether the break is in the annunciator-wire he must be notified from the central fire-station or office 1, and to effect this notification the telegraphic key 21 is brought into play.
  • the operator testing the line at the box 54 sends in any predetermined signal by manipulating the telegraphic key 60, which forms a part of the interior mechanism of most fire-alarm boxes, so as to indicate at the firest-ation or central oflice that a test is being made at the box 54 and that an alarm isnot being turned in.
  • the annunciator operates at'the central fire-statiomthe operator at the box 54: can be immediately notified of this by manipulating the telegraphic key 21 so as to sound a test-alarm by the gong or whistle 17 which upon 'being heard by the operator at the box 54E will indicate to him that the annunciator-wire is all right and that the break is therefore in the main line.
  • the lever 23 of the switch 24 will be 011 any of the points 25 and the circuit will include the battery 7,
  • wire 0 switch 9, gong 12, switch 14, wire 7;, gong or whistle 17, wire a, wire e, wire Z, telegraphic key 21, the wire m, switch 24, one of the wires n, one of the annunciator-wires 7a, the annunciator 18, and the wire j.
  • each firealarm box is of the usual construction, but is employed in connection with the system in the simplest possibleform, such as illustrated in Fig. 7 of the drawings.
  • the key 60 essentially comprises an oscillating key-lever 61, pivotally supportedTintermediate of its ends between a pair of metallic pivot-' posts 62 and provided at one end with a fin gerpiece 63.
  • the key-lever 61 of the telegraphic key 60 has attached thereto'one end of a retractile spring 64., the other end of which is fastened to the base 65 of the key and normally holds one end of the key-lever in contact with the contact-point 66, and at the same time normally holds the opposite end of the key-lever above and out of contact with the oppositely-located contact-point 67.
  • the contact-point 66 and the metallic pivotal support of the key-lever respectively, have connected therewith the branch wires a and a leading from the mainline terminals to and a within the fire-alarm boxes,the wire a being illustrated as branched from the terminal ctand the wire a is branched from the terminal a within each fire-alarm box.
  • the other contact-point 67 for the keylever 61 is designed to have connected thereto one end of a branch wire connection 70, which connects with the terminal of the annunciator-wire it within each box.
  • the telegraphic key 60 within each fire-alarm box has precisely the same three-wire connection therewith as the circuit-breaker within the box, and in its normal condition the telegraphic key allows the main-line circuit to be normally closed, as contemplated by the invention, and the annunciator-circuit to be normally open.
  • the main-line and .annunciator circuits are alternately opened and closed on the same principle as the circuit-breaker within the box, so that by operating the telegraphic key 60 the operator testing the line can readily send any predetermined signal to the operator at the central fire-station 1, whether there is a break in the line or not.
  • the switch-lever 2 After the test in the line has been made the switch-lever 2 is returned to the contact-point 5, for the reasons hereinbefore given, until the break has been repaired, and after this repair has been made the switch-lever. is returned to the contact-point 4 of the switch 3, which again sets the entire system in its normal working condition. Now should an alarm be sent'in to the central fire-station or office 1 by telephone the alarm for the box nearest the fire can be sounded by manipulating the key 21.
  • the telegraphic instrument 21 When it is desired tosend a special call for assistance, the telegraphic instrument 21 is again brought in to play, but the general gong or whistle 17 is cut out of use to avoidconfusion ofsignals by moving the lever 13 of the switch 14 onto the contact-point 15, which closes the circuit over the wires hand 6. Now should the special call be for an extra reel the lever 23 of the switch 24 is turned onto the contact-point 25, having a special-wire connection a with the particular drop or the annunciator, which when released would indicate that an extra reel was needed.
  • the working circuit includes the battery 7, the wire 0, switch '0, gong 12, switch 14, wire 7L, wire 6, wire Z, telegraphic instrument 21, wire m, switch 24, annunciator 1S, and wire], and after the telegraphic instrument has been used for the purpose indicated the general gong or whistle 17 is again brought into the circuit by moving the lever 13 back to the point 16.
  • Fig. 6 of the erent fire-stations are desely, as station No. 1, 2, and ese separate fire-stations is annunciator 18 and a staresponding to the annunciang 12 at the central fire-staie annunciators and stationluded in series circuits, so arm will be sounded at the f the different fire-stations.
  • Fig. 7 apparatus of all the stamaterial change is made in ctions illustrated in Fig. 7 ecause all of the stationerent stations are included kinga loop of the gongcentral station, so as to inn-gongs at the different stations, as clearly illustrated in Fig. (3 of the drawings.
  • the annunciators 18 throughout the system are similarly connected together by branching or looping the wire j from the central fire-station to the last ann unciator on the line of the annunciator-wire L.
  • a normally-closed main-line circuit including therein in series the fire-boxes, a station-gong and a general gong or Whistle, a normally open annunciator-circuit including the main line and an annunciator having a wire connection with each box and with the main line, and a circuitbreaker arranged in each box and adapted to alternately break the main-line circuit and close the annunciator-circuit, substantially as set forth.
  • a main-line circuit normally closed, and including in series the fire-alarm boxes, a station-gon g and a general gong or whistle, a normally open annunciator-circuit including the main line and an annunciator having separate wire connections with each box and a single wire connection with the main line, and means for alternately breaking the main-line circuit in each box, and closing the annunciator-circuit with either of the main-line terminals which enter the box, substantially as set forth.
  • a norm ally-closed main-line circuit including in series the firealarm boxes, a station-gong and a general gong or whistle, an annunciator-circuit including the main line and an annuneiator having a connection with the main line and separate wire connections with each box, and a circuit-breaker arranged in each box and having suitable connections with the wireterminals in the boxes to provide for alternately breaking the main-line circuit in each box, and closing the annunciator-ci-rcuit with either of the main-line terminals which enter the box, substantially as set forth.
  • a normally-closed main-line circuit including therein in series the fire-boxes, an annunciator-circuit having a separate wire connection for each box, and a circuit-breaker arranged in each box and suitably connected with the main line and the annunciator-wire terminals to provide for alternately breaking the main-line circuit in each box and closing the annunciatoncircuit with either of the main-line terminals which enter the box, substantially as set forth.
  • a circuit-breaker consisting of a suitably-rotated contact-disk arranged in said box and provided on its periphery with spaced groups of contact-teeth and an outer smooth contact portion at one side of said teeth, an auxiliary contact-disk arranged to rotate with and at one side of the toothed contact-disk, said auxiliary contact-disk being provided at one side with a series of offstanding contact pins projecting into the spaces between the teeth of the main contactdisk, a contact-brush connected with one of said main-line-wire terminals and normally bearing 011 the smooth contact portion of the main contact-disk, an oppositely-located contact-brush connected with the other of the said main-line-wire terminals and adapted to ride over the contact-teeth of the main contact-disk and provided with a supplemental brush normally contacting with said auxiliary contact-disk,
  • a normally-closed main-line circuit including therein in series the fire-boxes, and station-gong, a normally open annunciator-circuit including a portion of the main line and an annunciator having a connection with the main line and separate wire connections with each box a circuitbreaker arranged in "each box and having suitable connections with the wire-terminals therein to provide for alternatelybreaking the main-line circuit and closing the annunciator-circuit with either of the main-line terminals which enter the box, and a switch having a lever connected directly with the main line and separate contact-points respectively connected with one pole of the working battery, and with a continuation of the main line, so as to complete the circuit through the gong, substantially as set forth.
  • a normally open annunciator-circuit including a portion of the main line and an annunciator having a connection with the main line and separate wire connections
  • a circuit-breaker arranged in each box and suitably connected with the wireterminals therein to provide for alternately breaking the main-line circuit and closing the annunciator-circuit with either of the mainline terminals which enter the box, a switch having a lever directly connected with the main line and three separate contact-points respectively having wire connections with one pole of the battery, with the portion of the main line between the station-gong and the first fire-box, and with the portion ofthe main line between the battery and the station-gon g, a telegraphic instrument having a wire connection with the connection between the intermediate contact-point of the threepoint switch and the main line, and a switch having a separate wire connection with each drop
  • a normally-closed main-line circuit including therein in series the fire-boxes, a station-gong, and a general gong or whistle, a normally open annunciatorcircuit including a portion of the main line and an annunciator havinga connection with the main line and separate wire connections with each box, a circuit-breaker arranged in each box and having suitable connections with the wire-terminals therein, a switch having a lever connected directly with the main line and separate contact-points respectively connected with one pole of the working battery, and with the portion of the main line between the general gong or Whistle and the first box, a telegraphic instrument having a wire connection with the connection between the main line and one of the points of said switch, said telegraphic instrument being provided with a circuit-closing lever adapted to be thrown into contact with the point of the telegraphic instrument and having a shortcircuit wire connection with the wire leading from one pole of the battery to one point of the switch whose lever is connected with the main

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Description

(No Model.) a Sheets-Sheet n.
A. 0. ROGERS.
FIRE ALARM SYSTEM.
No. 573,924. Patente d Deo.29, 1896.
Jl are? 0. Rogers 3 Sheets-Sheet 2.
(No Model.)
A. 0. ROGERS.
FIRE ALARM SYSTEM. 9 No. 573,924. Patented Dec. 29,1896.
3 SheetS Sheet 3.
(No Model.)
A. 0. ROGERS.
FIRE ALARM SYSTEM.
'No. 573,924. Patented Dec. 29, 1896.
StaliowJifiB.
ception of showing the parts so positioned as UNIT D STATES PATENT Ii EEicE.
ALBERT C. ROGERS, OF PLAINFIELD, NEW JERSEY.
FIRE-ALARM SYSTEM.
SPECIFICATION forming part of Letters Patent No. 573,924, dated December 29, 1896.
Application filed January 25, 1896. Serial No. 576,887. (No model.)
To all whom it may concern..-
Be it known that I, ALBERT 0. ROGERS, a citizen of the United States, residing at Plainfield, in the county of Unionand State of New Jersey, have invented a new and useful Fire- Alarm System, of which the following is a specification.
This invention relates to fire-alarm systems for town and city use; and it has for its object to provide an improved system of this character whereby the different fire-stations and central oflice will be immediately notified of the number of the particular fire-alarm box from which the alarm was turned in without. having to wait until the gong in the station tolls off the number of the box, as is now the case in connection with most firealarm systems in general use.
The invention also contemplates, among other objects, an improved arrangement whereby even though a break should occur in the main line at either side of a particular fire-alarm box or in the annunciator-wire for such box the latter would not be rendered inoperative, but would still send in an alarm when manipulated in the usual way; and in the attainment of this very important object the invention also contemplates means for determining where the break is located, and also providing telegraphic communication throughout the'ent-ire system and also with the general gong or whistle, whereby an alarm may be sounded from the central station or office.
WVith these and other objects in view, which will readily appear as the nature of the invention is better understood, the same consists in the novel construction, combination, and arrangement of parts hereinafter more fully described, illustrated, and claimed.
In the drawings, Figure 1 is a diagrammatic view of the system shown in circuit with only the central station or oflice. Fig. 2 is a detail elevation of an ordinary fire alarm box equipped with a circuit-breaker constructed in accordance with this invent-ion. Fig. 3 is a detail elevation of the circuit-breaker, show ing the parts positioned so as to close the cir cuit between one of the main-line terminals in the box and the ann unciator-wire terminal. Fig.4 is a similar View to Fig. 3, with the exto close the circuit between the other of the main-line terminals in the box and the annunciator-wire terminal. Fig. 5 is a detail plan view of the circuit-breaker device. Fig.
6 is a diagrammatic View of the entire system,
which boxes are'connected in series by the main-line wire a.
It will of course be understood that the main-line wire a has two terminal connections with each of the fire-alarm boxes, and it will also be understood that any number of said boxes may be included in the circuit of the main line,but for convenience in understanding the system only three of the fire-alarm boxes are illustrated and are conveniently designated by the numerals which will also represent the numbers that the particular boxes are known by in the system.
The main-line wire a has one of its terminals lead to the fire-station 1, which will be understood to be the central fire-station or ofiice, and at which point this terminal of the main-line wire is suitably connected to one end of the switch-lever 2 of a three'point switch 3, provided with the three contactpoints 4, 5, and 6, with each of which points the swinging end of the switch-lever 2 is designed to contact to provide for making the proper circuit connections'in controlling the system. Normally when the system is in proper working condition the lever 2 is positioned to contact with the point 4., with which contact-point is connected one terminal of the battery-wire b, the other terminal of which wire connects to one pole of the working battery 7. The other pole of this battery has connected thereto one terminalof the batterywire 0, the other terminal of which wire connects with a switch-lever S of a two-point cutout switch 9, having the two contact-points 10 and 11. 9 has connected thereto one terminal of the The contactepoint 10 of the switch short-circuit wire d, the other terminal of Which connects with the wire 6, which wire is connected with the intermediate contactpoint 5 of the switch 3, and at its terminal opposite the connection with the point 5 with the main-line wire a, near the terminal thereof, opposite the terminal connected with the switch-lever 2.
The contact-point 11 of the switch 9 has connected thereto one terminal of the gon g-wiref, leading to the electric station-gen g 12, which is arranged at the fire-station with the other controlling apparatus and is set on a closed circuit, so as to operate and sound an alarm when the circuit in which the gong is included is broken. A gong-wire 9 leads from the station-gong 12 to the switch-lever 13 of a cutout switch 14, providedwith the two contactpoints 15 and 16, respectively. The contactpoints 15 and the switch 1t have connected thereto a short-circuit wire it, which also connects with the wire 6, and the contact-point 16 has connected thereto one terminal of the wire '11, the other terminal of which connects with an electrical general gong or whistle 17, to the controlling mechanism of which is also connected the terminal of the main-line wire a 0p posite the terminal connected with the switch The general gong or whistle 17 is illustrated as being an ordinary steam-whistle controlled by suitably-operated mechanism which is set on a closed circuit, so as to operate and sound the whistle when the circuit in which such whistle is included is broken, and at this point it may be observed that steam-whistles of this character are isolated at some convenient point in the city or town, so that the fire-alarm can be easily heard within any reasonable dis tance, but it will of course be understood that the whistle may be substituted for by an ordinary electric gong intended to accomplish the same result.
The pole of the working battery 7, to which the wire Z) leads, also has connected therewith one terminal of the return-wire j of an ordinary annunciator or indicator 18, pro-,
vided with any suitable number of drops 19, according to the number of fire-alarm boxes in the system and the number of special calls desired to be indicated by the annunciator, and said annunciator is also provided with the usual bell 20, which rings an alarm whenever one of the drops is released. The annunciator 18 is illustrated as being provided with four drops, one each for the fire- alarm boxes 52, 53, and 54, and one for a special call, such as for an engine, a reel, &c.; and it will of course be understood that the annunciator will be provided with any number of drops for special calls and with the requisite number of drops for the fire-alarm boxes. The drops 19 for the lire-alarm boxes are provided with the numbers of these boxes, so that the moment a drop is released and shows its number at the fire-station it will immediately indicate the number of the firealarm box from which the alarm was turned in, so that the firemen will not be compelled to wait until the gong has tolled off the num-' ber of the fire-alarm box before starting to the fire, which is an item of considerable importance in fire-alarm systems.
Each of the fire-alarm boxes has a separate annunciator-wire leading thereto, which annunciator-wire also connects with the annunciator and controls the particular drop having the same number as the fire-alarm box to which the wire leads, so it will therefore be seen that there is a direct annunciator-wire connection between the annunciator at the fire-station and each fire-alarm box, although it will be understood that the entire series of annunciator-wires may be run out from the station in a cable, as is customary in stringing wires.
In connection with the apparatus that has just been described as being located at the central fire-station or office an ordinary telegraphic key 21 is employed. The key proper of the telegraphic key has a wire connection 1 with the wire a, and the contact-point 22 of the telegraphic key has connected thereto one terminal of the switch-wire m the other ter minal of which wire connects with a switchlever 23 of a switch 2t, provided with a numberof separate contact-points 25, which correspend in number to the number of fire-alarm boxes and special calls which are indicated by the annunciator 18. The separate contact-points 25 of the switch 24 have separate wire connections a, respectively, with each of the annunciator-wires and with the special drop which the annunciator is illustrated as being provided with, and the special-wire connection between one of the contact-points of the switch 24 and the annunciator may be additionally designated by the referencecharactcr 92/.
The manner of employing the telegraphic key will be fully set forth; but at this point it is to be noted that the said key is provided with a pivoted circuit-closing lever 26, that is adapted to be thrown into contact with the contact-point 22 of the key, and which has connected therewith a short-circuit wire 0, which wire also connects with the battery-wire b, as will be hereinafter more particularly referred to.
Referring now to the particular wire connections with each fire-alarm box, it will be understood that such fire-alarm boxes are provided with the usual mechanism for turning in an alarm, and the present invention does not contemplate the material changing of this mechanism, so Fig. 2 of the drawings simply indicates diagrammatically in dotted lines the mechanism 27, which is found in all firealarm boxes.
The only improvement or addition which the present invention contemplates in connection with fire-alarm boxes is a circuitbreaker 28, which circuit-breaker necessarily provides for a different arrangement of the wire-terminals leading into the boxes. The
circuit-breaker 28 essentially consists of a contact-disk 29, mounted on one of the shafts of the mechanism 27, so that when the a controlling lever or hook of the mechanism is pulled to set the latter in motion a rotation will necessarily be imparted to the contact-disk 29. The contact-disk 29 is provided on its periphery with spaced groups of contact-teeth 30, which teeth are grouped in substantially the same manner as in the circuitbreakers in common use, it being understood that the number of teeth in each group corresponds to one of the figures of the particular number of the fire-alarm box in which the circuit-breaker is arranged.
As clearly illustrated in the drawings, the disk 29 is represented as being provided with spaced groups of respectively five and two teeth, which make the number 52, which is the number of the fire-alarm box illustrated in Fig. 2 of the drawings. The rotatingcontact-disk 29 is suitably insulated from the shaft 30 and is provided at one side of the teeth 30 with an outer smooth contact portion 31, on which bears one end of the spring contact-brush 32, to whichis connected one of the terminals ct of theline-wire leading into the box, and the other terminal CL2 of the line-wire leading into the box is connected to the opposite spring contact-brush 33, one end of which is adapted to bear on and ride over the contact-teeth 30 of the disk. The wire-terminal ct, connected with the brush 32, is always the terminal of that portion of the main-line wire which leads from the general gong or whistle, in order that the proper circuit connections may be made, as will be hereinafter more fully understood, and in conjunction with the brushes 32 and 33, connected, respectively, with the wire-terminals c and a is employed an annunciator-wire brush 3*, to which connects the terminal of the annunciator-wire leading into the box.
The annunciator-wire brush 34 is also adapted to ride over and contact with the contact-teeth of the disk, but does not contact with the disk between the groups of teeth. So, therefore, it will be observed by reference to Fig. 2 of the drawings that when the mechanism in the fire-alarm box is at rest the annunciator-circuit will remain open while the main-line circuit will be closed through the medium of the metallic disk 29, which provides a metallic connection between the brushes 32 and 33 for the main-line wire, and since the main-line circuit is normally closed in the manner described both of the brushes 32 and 33 are designed to normally always contact with the disk.
At one side of the rotating contact-disk 29 is located an auxiliary contact-disk 35, which is insulated from the shaft 30 in the same manner as the disk 29, and is provided at one side with a series of offstanding contact-pins 36, which project into the spaces between the teeth 30 of the disk 29, and said auxiliary contact-disk 35 has normally contactintherewith the supplemental contact-brush 33, forming a part of the brush 33, which rides over the teeth 30. Now it will be observed that as the disk 29 rotates and the brush. 33 rides over the teeth 30 the circuit on the main line will be broken as many times as fire-alarm box from which the alarm is turned in. As the rotation of the disk 29 continues it will therefore be seen that there is an alternate breaking of the main-line circuit and a closing of the annunciator-circuit, although the interval of time between these two operations will be scarcely noticed at the station, so that the annunciator. will practically indicate the number of the fire-alarm box at the moment the alarm is turned in and-when the station-gong has just commenced to toll off the number.
It will be further noticed that as the disk 29 continues to rotate the brush when it leaves each tooth 30 drops onto one of the contact-pins 36 between the teeth, so that the main-line circuit remains broken while the annunciator-circuit is closed, and in the moment of time when the tip end of the brush is passing across the space from one of the contact-pins to one of the teeth of the disk 29 the annunciator-wire brush 34 will drop in contact with one of the pins of the contact disk 35 and will thereby close the annunciator-circuit over the wire 70 and that portion of the main-line wire having a terminal connection a with the supplemental brush 33, contacting with the disk 35, carrying the pins 36. hen the annunciator-circuit is closed by the means just described in the fire-alarm box, the annunciator will not operate, but, as will be explained in connection with the ma nipulation of the switch 3, this manner of closing the annunciator-circuit is important to render a fire-alarm box operative when the main line has broken at one side of the same. With the entire system in perfect condition, without any breaks ineither the main line or in any of theannunciator-wires, when the alarm is turned in from said box No. 52 the. disk 29, rotating in such box, willbreak the main-line circuit five times and then two times in the manner which is well understood, so as to cause the station-gong 12 and the general gong or whistle 17 to sound the num ber 52, thereby indicating which fire-alarm box the alarm was turned in from, and the main-line circuit referred to includes the battery 7, wire a, cut-out switch 9, station-gong 12, cut-out switch 14, general gong or whistle 17, the main-line wire a, switch 3, and battery-wire 1). During the operation of the mechanism in the fire-alarm box referred to the annunciator-circuit will be closed at rapid intervals through the brushes 32 and 34, wire 70, annunciator 18, wire j, battery 7, wire 0, cut-out switch 9, station-gong 12, cut-out switch 14, wire 1', general gong or whistle 17, and wire a, including the box-terminal a of the latter.
Since the circuit of the main line is normally closed, it will of course be understood that should any break occur in the main line at a point between any two boxes the stationgong 12 and the general gong or whistle 17 would necessarily sound one alarm, which would at once indicate at the station or central office that a break had occurred somewhere in the main line. Immediately upon receiving this knowledge at the central station the switch-lever 2 is swung in contact with the contact-point 5 of the switch 3, thereby, through the medium of the wire c, connecting all of the boxes at the side of the break farthest from the gong or whistle 17 with the terminal of the main-line wire which connects with such gong or whistle. Assuming the break to be at the point 13 between the boxes 53 and 54, or at any other point, the switching of the circuit in the manner described will provide means whereby all of the firealarm boxes will operate in the same manner as if no break had occurred. For instance, taking the box 53, which will operate in the same manner as the box 52, with the break B located between the boxes 53 and 54, when the alarm is turned in from the box 53, it being remembered that the switch-lever 2 contacts with the point 5, the main-line circuit will be combined with the annunciator-circuit to complete a continuous circuit, it being noted that with respect to the box 53 that portionof the main line is broken which has a terminal connection a with the brush Consequently as the disk 29 continues to rotate the circuit will be alternately opened and closed between the brushes 32 and 34, and this circuit will include the battery 7, wire a, switch 9, station-gong 12, switch 14, wire 2', general gong or whistle 17, wire a, and terminal ct of said wire, annunciator-wire 7t, annunciator 18,
and wire j. Now with respect to the fire-alarm box 54, which is at the opposite side of the break B to the box 53, it will be noted that that portion of the main-line wire is broken which has a terminal connection a with the brush 32. It will therefore be seen that when the alarm is turned in at the box 54 the circuit will be alternately opened and closed between the brushes 33 and 34, the brush 33 having the supplemental brush 33, as hereinbefore described. Since the circuit is opened and closed between the brushes 33 and 34 when the alarm is turned in from the box 54, at one side of the break B, the circuit will include the battery 7, wire 0, switch 9, station-gong 12, switch 14, wire '5, general gong or whistle 17, wire a, wire 2, lever 2 of switch 3, wire a, terminal a in box 54, annunciator-wire for said box, annunciator 18, and wirej.
From the foregoing it will be apparent that no matter where the break in the main line occurs the entire system, including all of the fire-alarm boxes, is rendered operative by a simple manipulation of the lever 2 of the switch 3 to contact with the point 5 of said switch, and at this point attention will be directed to the means for ascertaining or testing the system to find out where the break is located.
It may be briefly noted that should an annunciator-wire break the failure of the a11- nunciator to operate for a particular box would at once indicate that the annunciaton wire for such box is the wire which is broken and the defect can be immediately repaired; but with respect to a break in the main line the first step for determining Where this break is located is to move the switch-lever 2 around to the contact-point 6, which has a wire connection 19 with the wire 0, connected with one pole of the battery 7.
WVith the switch-lever 2 positioned on the contact-point 6 the operation of none of the boxes to sound an alarm is prevented, but the boxes 52 and 53, at the side of the break nearest the gong or whistle 17 will sound an alarm not only through the annunciator, but also through the gong 12 and the gong or whistle 17 while the box 54 will only sound an alarm through the annunciator. so when the operator has tested the box 53 and then comes to the box 54 and 'fails to hear the gong or whistle 17 he knows at once that the break in the main line is between the boxes 53 and 54. In this testing operation the circuit for the boxes 52' and 53 is completed through the battery 7, wire 0, switch 9, gong 12, switch 14, wire '6, gong or whistle 17, wire a, annunciator-wire 7.0, annunciator 18, and wire j, while the circuit for the box 54 is completed through the battery 7, wire 0, wire 1), switch 3, wire Ct, box 54, wire 70, annunciator l3, and wire Assuming that the operator is still testing the line at the box 54 and the break remains in the main line at the point B, the annunciator will operate at the fire-station, but the operator at the box 54 will not know this, because the general gong or whistle 17 will not sound an alarm. Now before the operator at the box 54 can determine whether the break is in the annunciator-wire he must be notified from the central fire-station or office 1, and to effect this notification the telegraphic key 21 is brought into play. In the first place, however, the operator testing the line at the box 54 sends in any predetermined signal by manipulating the telegraphic key 60, which forms a part of the interior mechanism of most fire-alarm boxes, so as to indicate at the firest-ation or central oflice that a test is being made at the box 54 and that an alarm isnot being turned in. If the annunciator operates at'the central fire-statiomthe operator at the box 54: can be immediately notified of this by manipulating the telegraphic key 21 so as to sound a test-alarm by the gong or whistle 17 which upon 'being heard by the operator at the box 54E will indicate to him that the annunciator-wire is all right and that the break is therefore in the main line. In this manipulation of the telegraphic key 21 the lever 23 of the switch 24 will be 011 any of the points 25 and the circuit will include the battery 7,
the wire 0, switch 9, gong 12, switch 14, wire 7;, gong or whistle 17, wire a, wire e, wire Z, telegraphic key 21, the wire m, switch 24, one of the wires n, one of the annunciator-wires 7a, the annunciator 18, and the wire j.
The telegraphic key within each firealarm box is of the usual construction, but is employed in connection with the system in the simplest possibleform, such as illustrated in Fig. 7 of the drawings. In this figure the key 60 essentially comprises an oscillating key-lever 61, pivotally supportedTintermediate of its ends between a pair of metallic pivot-' posts 62 and provided at one end with a fin gerpiece 63. Atone side of its pivotal support the key-lever 61 of the telegraphic key 60 has attached thereto'one end of a retractile spring 64., the other end of which is fastened to the base 65 of the key and normally holds one end of the key-lever in contact with the contact-point 66, and at the same time normally holds the opposite end of the key-lever above and out of contact with the oppositely-located contact-point 67. The contact-point 66 and the metallic pivotal support of the key-lever, respectively, have connected therewith the branch wires a and a leading from the mainline terminals to and a within the fire-alarm boxes,the wire a being illustrated as branched from the terminal ctand the wire a is branched from the terminal a within each fire-alarm box. The other contact-point 67 for the keylever 61 is designed to have connected thereto one end of a branch wire connection 70, which connects with the terminal of the annunciator-wire it within each box.
By reason of the branch Wire connections described it will be observed that the telegraphic key 60 within each fire-alarm box has precisely the same three-wire connection therewith as the circuit-breaker within the box, and in its normal condition the telegraphic key allows the main-line circuit to be normally closed, as contemplated by the invention, and the annunciator-circuit to be normally open. During the manipulation of the lever 61 of the telegraphic key 60 within eachbox it will be obvious that the main-line and .annunciator circuits are alternately opened and closed on the same principle as the circuit-breaker within the box, so that by operating the telegraphic key 60 the operator testing the line can readily send any predetermined signal to the operator at the central fire-station 1, whether there is a break in the line or not.
.box nearest the fire.
After the test in the line has been made the switch-lever 2 is returned to the contact-point 5, for the reasons hereinbefore given, until the break has been repaired, and after this repair has been made the switch-lever. is returned to the contact-point 4 of the switch 3, which again sets the entire system in its normal working condition. Now should an alarm be sent'in to the central fire-station or office 1 by telephone the alarm for the box nearest the fire can be sounded by manipulating the key 21. Itis first necessary, however, to move the switch-lever 23 to the contact-point 25 having awire connection with the particular drop carrying the number of the fire-alarm Vhen this portion of the circuit has been closed, the next step necessary is to swing the circuit-closing lever 26 in contact with the contact-point 22 of the key 21, which cuts out all of the fire-alarm boxes and short-circuits the main line by providing the short circuit, which includes the battery 7, wire 0, switch 9, gong 12, switch 14, wire 1', gong or whistle 17, wire a, wire 0, wire Z, key 21, wire 0, and battery-wire b. This short-circt i iting of the main line is absolutely necessary in this operation, so that an. alarm will not be sounded when the main-line circuitis broken by shifting the lever 2 from the point at to the point 5, which is necessary to make the proper circuit connection so that the alarm can be telegraphed to the general gong or whistle. Now, assuming that the lever 2 has been thrown to the point 5, the operator depresses the key of the telegraphic instrument 21 at the same moment he throws the lever 26 out of contact with the point 22, so that on the first sound of the gong or whistle l7 theannunciator 18 will work, and by continuing to manipulate the key of the telegraphic instrument the number of the firealarm box nearest the fire will be sounded by the annunciator 1S, thestation-gong 12, and also the general gong or whistle.
When it is desired tosend a special call for assistance, the telegraphic instrument 21 is again brought in to play, but the general gong or whistle 17 is cut out of use to avoidconfusion ofsignals by moving the lever 13 of the switch 14 onto the contact-point 15, which closes the circuit over the wires hand 6. Now should the special call be for an extra reel the lever 23 of the switch 24 is turned onto the contact-point 25, having a special-wire connection a with the particular drop or the annunciator, which when released would indicate that an extra reel was needed. Now when this indication has been made by depressing the key of the telegraphic instrument to close the circuit the lever 23 is next moved to the contact-point 25, having a wire connection with the particular drop of the annunciator indicating the number of the firealarm box nearest the fire where the extra reel is needed, so it is therefore simply necessaryafter a readjustment of the lever 23 to again depress the key of the telegraphic in- IIO strument to indicate, the number of the firealarm box. In this manipulation of the telegraphic instrument the working circuit includes the battery 7, the wire 0, switch '0, gong 12, switch 14, wire 7L, wire 6, wire Z, telegraphic instrument 21, wire m, switch 24, annunciator 1S, and wire], and after the telegraphic instrument has been used for the purpose indicated the general gong or whistle 17 is again brought into the circuit by moving the lever 13 back to the point 16.
On Sundays and holidays it is sometimes desirable th atsim ply a still alarm be sounded at the fire-station by the annunciator and station-gong, and to secure this result it is only necessary to cut out the general gong or whistle 17 by means of the switch 1 1 in the manner already described, and if there should be any defect in the line or apparatus between the switch 9 and the point where the wire 6 connects with the Wire a both the stationgong 12 and the general gong or whistle are cut out of the main circuit by moving the lever 8 of the switch 9 onto the point 10, and the circuit will then be completed over the wires (1 and e in connection with the main-line wire a.
For the purpose of making the operation of the system perfectly clear, and particularly the manner of testing the system, the detail de *ription has been directed especially to the m as illustrated in Fig. 1 of the drawnasmuch as this figure of the drawings \tges the central fire-station having all paratus necessary to provide for teststem and for special calls and the e at the same time having the same as the other fire-stations. Thereie central station 1 is illustrated with the same apparatus as the stations it will be understood tion of the manner of using 'urni-ng in an alarm will anhe fire-stations included in entire system has all of the us connected up in series, diagrammatic view, Fig.
natic view, Fig. 6 of the erent fire-stations are desely, as station No. 1, 2, and ese separate fire-stations is annunciator 18 and a staresponding to the annunciang 12 at the central fire-staie annunciators and stationluded in series circuits, so arm will be sounded at the f the different fire-stations.
apparatus of all the stamaterial change is made in ctions illustrated in Fig. 7 ecause all of the stationerent stations are included kinga loop of the gongcentral station, so as to inn-gongs at the different stations, as clearly illustrated in Fig. (3 of the drawings. The annunciators 18 throughout the system are similarly connected together by branching or looping the wire j from the central fire-station to the last ann unciator on the line of the annunciator-wire L.
From the foregoing it is thought the construction and operation of the herein-described fire-alarm system will be readily apparent to those skilled in the art, and I would have it understood that various changes in the form, proportion, and the minor details of construction may be resorted to without departing from the principle or sacrificing any of the advantages of this invention.
Having thus described the invention, what is claimed, and desired to be secured by Letters Patent, is
1. In a fire-alarm system, a normally-closed main-line circuit including therein in series the fire-boxes, a station-gong and a general gong or Whistle, a normally open annunciator-circuit including the main line and an annunciator having a wire connection with each box and with the main line, and a circuitbreaker arranged in each box and adapted to alternately break the main-line circuit and close the annunciator-circuit, substantially as set forth.
2. In a fire-alarm system, a main-line circuit, normally closed, and including in series the fire-alarm boxes, a station-gon g and a general gong or whistle, a normally open annunciator-circuit including the main line and an annunciator having separate wire connections with each box and a single wire connection with the main line, and means for alternately breaking the main-line circuit in each box, and closing the annunciator-circuit with either of the main-line terminals which enter the box, substantially as set forth.
3. In a fire-alarm system, a norm ally-closed main-line circuit including in series the firealarm boxes, a station-gong and a general gong or whistle, an annunciator-circuit including the main line and an annuneiator having a connection with the main line and separate wire connections with each box, and a circuit-breaker arranged in each box and having suitable connections with the wireterminals in the boxes to provide for alternately breaking the main-line circuit in each box, and closing the annunciator-ci-rcuit with either of the main-line terminals which enter the box, substantially as set forth.
a. In a fire-alarm system, a normally-closed main-line circuit including therein in series the fire-boxes, an annunciator-circuit having a separate wire connection for each box, and a circuit-breaker arranged in each box and suitably connected with the main line and the annunciator-wire terminals to provide for alternately breaking the main-line circuit in each box and closing the annunciatoncircuit with either of the main-line terminals which enter the box, substantially as set forth.
5. The combination with a signaling-box;
of a main-line signal-circuit having two wireterminals entering said box, an annunciatorcircuit having a singlewire-terminal entering said box, and a circuit-breaker consisting of a suitably-rotated contact-disk arranged in said box and provided on its periphery with spaced groups of contact-teeth and an outer smooth contact portion at one side of said teeth, an auxiliary contact-disk arranged to rotate with and at one side of the toothed contact-disk, said auxiliary contact-disk being provided at one side with a series of offstanding contact pins projecting into the spaces between the teeth of the main contactdisk, a contact-brush connected with one of said main-line-wire terminals and normally bearing 011 the smooth contact portion of the main contact-disk, an oppositely-located contact-brush connected with the other of the said main-line-wire terminals and adapted to ride over the contact-teeth of the main contact-disk and provided with a supplemental brush normally contacting with said auxiliary contact-disk, and an annunciator-wire brush connected with the annunciator-wire terminal and also adapted to ride over said contact-teeth and said contact-pins,substantially as set forth.
6. In a fire-alarm system, a normally-closed main-line circuit including therein in series the fire-boxes, and station-gong, a normally open annunciator-circuit including a portion of the main line and an annunciator having a connection with the main line and separate wire connections with each box a circuitbreaker arranged in "each box and having suitable connections with the wire-terminals therein to provide for alternatelybreaking the main-line circuit and closing the annunciator-circuit with either of the main-line terminals which enter the box, and a switch having a lever connected directly with the main line and separate contact-points respectively connected with one pole of the working battery, and with a continuation of the main line, so as to complete the circuit through the gong, substantially as set forth.
7. In a fire-alarm system, anormally-closed main-line circuit including therein in series, the fire-boxes, a working battery, anda station-gong, a normally open annunciator-circuit including a portion of the main line and an annunciator having a connection with the main line and separate wire connections With each box, a circuit-breaker arranged in each box and suitably connected with the wireterminals therein to provide for alternately breaking the main-line circuit and closing the annunciator-circuit with either of the mainline terminals which enter the box, a switch having a lever directly connected with the main line and three separate contact-points respectively having wire connections with one pole of the battery, with the portion of the main line between the station-gong and the first fire-box, and with the portion ofthe main line between the battery and the station-gon g, a telegraphic instrument having a wire connection with the connection between the intermediate contact-point of the threepoint switch and the main line, and a switch having a separate wire connection with each drop of the annunciator, and a single wire connection with the telegraphic instrument, substantially as set forth.
8. In a fire-alarm system, a normally-closed main-line circuit including therein in series the fire-boxes, a station-gong, and a general gong or whistle, a normally open annunciatorcircuit including a portion of the main line and an annunciator havinga connection with the main line and separate wire connections with each box, a circuit-breaker arranged in each box and having suitable connections with the wire-terminals therein, a switch having a lever connected directly with the main line and separate contact-points respectively connected with one pole of the working battery, and with the portion of the main line between the general gong or Whistle and the first box, a telegraphic instrument having a wire connection with the connection between the main line and one of the points of said switch, said telegraphic instrument being provided with a circuit-closing lever adapted to be thrown into contact with the point of the telegraphic instrument and having a shortcircuit wire connection with the wire leading from one pole of the battery to one point of the switch whose lever is connected with the main line, and a switch having a separate wire connection with each drop .of the a11- nunciator and a single wire connection with the telegraphic instrument, substantially as set forth.
In testimony that I claim the foregoing as my own I have hereto affixed my signature in the presence of two witnesses.
ALBERT 0. ROGERS.
lVi tnesses JOHN H. SIGGERS, G. O. SHOEMAKER.
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